The characteristics of the problem are always influenced by some factors. We find out these factors through brainstorming, and together with the eigenvalues, we call the graph with clear hierarchy, clear organization and important factors as the characteristic factor graph. Because of its shape like fishbone, it is also called fishbone diagram (hereinafter referred to as fishbone diagram), which is an analytical method to see the essence through phenomena. At the same time, fishbone diagram is also used in production, which directly represents the process of production workshop.